化的Pd催化分子间化:发现酸可以在复合体中进行转化
Jingjun Yin1, Stephen L Buchwald
1Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Journal of the American Chemical Society
|May 23, 2002
概括
一种新的催化方法使得化与胺的有效分子间合,形成关键的碳键. 这种多功能反应显示了广泛的功能组耐受性和使用低催化剂负载的高产量.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 有机金属化学 有机金属化学
背景情况:
- 在有机合成中,开发高效的碳- (C-N) 键形成的催化系统至关重要.
- 催化交叉合反应是构建C-N键的强大工具,但通常需要特定的条件或连接体.
- 使用像Xantphos这样的素配体可以显著影响催化剂的活性和选择性.
研究的目的:
- 开发一种使用Xantphos/Pd催化剂进行烯化物和胺分子间合的通用和高效方法.
- 调查开发的催化系统的范围和功能组兼容性.
- 准备和表征一种特定的复合物,参与催化循环.
主要方法:
- 在Xantphos/Pd催化剂系统的存在下,使用烯化物和胺进行了分子间合反应.
- 进行了反应条件的优化,包括度和催化剂负载.
- 一个复合物, (Xantphos) Pd ((4-cyanophenyl) ((Br),被合成和特征,包括X射线晶体分析.
主要成果:
- 香/Pd催化剂系统促进了烯化物和胺的分子间合,产生良好的至优良的产量 (1-4 mol % Pd催化剂).
- 该方法表现出良好的功能组兼容性,并且对硫胺,氧利丁和尿素的化有效.
- 合成的复合物 (Xantphos) Pd ((4-cyanophenyl) ((Br),被证明是合反应的活性催化剂.
结论:
- 已经建立了一种强大且通用的催化方法,用于在化和胺之间形成C-N键.
- 反应的效率对度和催化剂负载是敏感的,这突显了反应优化的重要性.
- 该研究通过制备和表征具有独特结构的关键中间体,提供了对催化机制的洞察.
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